STMicroelectronics LD59030DTPU33R

Overview

LD59030DTPU33R from STMicroelectronics is a 3.3 V, 300 mA ultra-low-dropout linear regulator in DFN4 1×1 mm package, featuring 135 mV typical dropout at full load, ±1 % output voltage accuracy at 25 °C, and 28 µA typical quiescent current at no load. It integrates logic-controlled shutdown, internal soft-start, thermal protection, and optional output discharge-designed for space-constrained, battery-powered systems requiring stable low-noise power.

For engineers reviewing the LD59030DTPU33R datasheet, LD59030DTPU33R pinout, LD59030DTPU33R application, or LD59030DTPU33R equivalent, key selection criteria include dropout performance at 300 mA, PSRR (75 dB @ 1 kHz), ceramic capacitor compatibility (≥0.47 µF), enable logic interface, and thermal behavior across –40 °C to 125 °C junction range.

Technical Context

The LD59030DTPU33R employs a bandgap-referenced op-amp control loop with internal bias generator and thermal foldback protection. Its architecture supports stable operation with low-ESR ceramic output capacitors as small as 0.47 µF, enabled by optimized phase margin design and integrated soft-start circuitry that limits inrush current without external components.

Enable functionality is implemented via a dedicated EN pin (logic-high active), directly controlling internal pass transistor gate drive and optionally activating an integrated discharge MOSFET (present in "D" suffix variants like this one). The thermal pad is electrically tied to GND and rated for 1000 V HBM ESD tolerance.

Key Specifications

Pinout & Package

LD59030DTPU33R is housed in a thermally enhanced DFN4 1×1 mm package with exposed thermal pad (tied to GND). The package supports reflow soldering per JEDEC J-STD-020 and features 0.65 mm pitch, 4 signal terminals, and a bottom-side thermal pad for improved heat dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout linear regulator applications.

Compared with XC6210B332MR-G and BD3508EUV-M, LD59030DTPU33R uniquely combines ultra-low dropout (135 mV), integrated soft-start, and output discharge in a 1×1 mm footprint-making it optimal for compact, battery-sensitive designs requiring controlled power sequencing and fast rail collapse.

Availability

LD59030DTPU33R is available at Aetrix Electronics and suitable for wearable health monitors, automotive body control modules, industrial wireless sensor nodes, and medical point-of-care diagnostic devices requiring stable component supply with tight voltage tolerance and low quiescent current.

Supply support for LD59030DTPU33R includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing silicon solutions for automotive, industrial, and consumer markets since 1987.

The LD59030 belongs to ST's high-accuracy, ultra-low-I_Q LDO family-engineered specifically for battery-powered and space-constrained applications demanding precision regulation, minimal power loss, and robust transient response.

FAQ

What is the minimum input voltage required for stable 3.3 V output at 300 mA?

The LD59030DTPU33R requires VIN ≥ VOUT + VDROP. With 135 mV typical dropout at 300 mA and 3.3 V nominal output, minimum stable input is 3.435 V. At worst-case 200 mV dropout (–40 °C to 85 °C), input must be ≥3.5 V. Below this, regulation fails and output drops linearly with input.

Can LD59030DTPU33R operate with a 0.22 µF output capacitor?

No. The datasheet specifies a minimum 0.47 µF ceramic capacitor (X5R/X7R) for stability across temperature and load. Using 0.22 µF risks oscillation or poor transient response, especially at high temperatures or light loads, as confirmed by Figure 15 (stability area vs. COUT/ESR).

How does the output discharge feature behave during shutdown?

When EN is pulled low, the internal discharge MOSFET activates and sinks current from VOUT to GND. For a 10 µF output capacitor charged to 3.3 V, discharge completes in <1 ms (RON ≈120 Ω). This prevents residual voltage from interfering with downstream logic states or causing latch-up during system reset.

Is the thermal pad electrically isolated or must it be connected to GND?

The thermal pad is internally connected to the die substrate and must be soldered to a GND plane. Per Table 1 and DS12219 Rev 8 page 3, it serves as both thermal conduction path and ESD protection node (rated for 1000 V HBM), and leaving it unconnected degrades thermal performance and compromises ESD robustness.